4.6 Watersheds Study Guide

Put hay / grass material around the drains to stop the sediment going down the drains.
Maintain zones of grass at least 100m wide on the sides of streams in the area

A team at a university in Pennsylvania has concerns about the health of streams in a watershed because of the various land uses in the area. There has been an increase in road repair work, and the area has many dairy farms. What would be the most effective at preventing sediment runoff into the streams of the watershed?

I. the soil in floodplains is usually fertile

Ii. the terrain in the floodplains tends to be flat.

Iii. Floodplains are close to rivers for transportation.

Name the three reasons that human populations historically have settled in floodplains?

The damming of the Colorado River led to a change in stream flow, preventing river water and sediments from reaching the delta area.

Hoover Dam is the largest dam in the United States, built on the Colorado River to supply hydroelectric power and flood control. What is a downstream environmental effect of Hoover Dam on the Colorado River watershed?

Surface water and stormwater runoff will drain downstream within the watershed boundaries, so it is important to understand the flow of water through the watershed.

Why is it important in understanding a watershed and its boundaries is important in designing housing developments along a river?

The land use upstream of the river and water quality indicators in streams that run downstream into the river

What should be included in a watershed map to best determine the non-point source of a pollutant, such as fertilizer, found in a river?

runoff

What's an example of a nonpoint source